DEPOSITION AND DIAGENESIS OF THE BLOSSOM SAND, PANOLA COUNTY, TEXAS

The Blossom Sand is a glauconitic sandstone found in the Upper Cretaceous Austin Group of the East Texas Basin. The Blossom Sand which exists in the subsurface of east Texas, western Louisiana, and southwest Arkansas, crops out in northeast Texas.

Works detailing gas discoveries and production from the Blossom Sand have described it as a shallow marine sandstone. However, such works reference no research to support this claim and are based upon mud logs dating back to the 1920s. In this study, five cores were used to determine the depositional environment and clay diagenesis of the Blossom Sand in Panola County, TX. Lithologies and sedimentary sequences were determined with a combination of core descriptions and x-ray diffraction and handheld x-ray fluorescence. Isopach and structure maps were constructed in Petra by correlating well logs also from Panola County.

The mineralogy of the Blossom Sand consists primarily of quartz, glauconite, illite, and smectite. The elemental data from x-ray fluorescence displays variation in these minerals moving down the core. Isopach and structure maps display the Blossom Sand as having a trend of southwestward dip with it thinning in the same direction. The continuity of the Blossom Sand combined with the geochemical data and its trend of thickening toward the northeast support the hypothesis that the sands were sourced from fluvial systems stemming from the Ouachita Mountains. The glauconite resulted from the alteration of fecal pellets that were deposited at the same time as the sands. Fossils of shallow marine organisms and sedimentary structures found in the core indicate that the sands were deposited in a nearshore tidally influenced environment.